This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A183769 #7 Jan 14 2017 09:38:39 %S A183769 160,14784,1555840,173065984,19855042560,2323234636800, %T A183769 275588031713280,33021546171494400,3987331943727333376, %U A183769 484411726089672392704,59141557731461248942080,7250125459895693790478336 %N A183769 1/32 the number of (n+1) X 7 binary arrays with equal numbers of 2 X 2 subblocks with sum mod two being 0 and 1. %C A183769 Column 6 of A183772. %H A183769 R. H. Hardin, <a href="/A183769/b183769.txt">Table of n, a(n) for n = 1..75</a> %e A183769 Some solutions for 3 X 7: %e A183769 ..0..0..0..1..0..0..1....0..0..0..0..0..1..0....0..0..0..0..1..1..0 %e A183769 ..0..1..1..0..0..1..1....0..0..1..0..0..0..1....1..1..0..1..1..0..1 %e A183769 ..0..0..0..1..1..1..1....1..0..1..1..0..0..1....1..1..0..0..0..1..1 %K A183769 nonn %O A183769 1,1 %A A183769 _R. H. Hardin_, Jan 06 2011